Radio pick-up system



June 24, 1930*. 1H, F, ELLITT 1,768,196

RADIO PICK-UP SYSTEM` @T/53" f 4 VJ v ,6 @www if I L fi V PIE-; 3,/ M ,Z f 4 HIS ATTORNEY June 24, 1930. 1,768,196

H. F, ELLIOTT RADIO PTU-OUP SYSTEM Filed March ll, 192'? 2 Sheets-Sheet L eww HIS ATTO R NEY Patented `une 24, 193

[UNITED STATES PATENT OFFICE.

HAROLD F. ELLIOTT, OF PALO ALTO, CALIFORNIA, ASSIGNOR, BY DIRECT' AND MESNE ASSIGNMENTS, TO VICTOR TALKING MACHINE COMPANY,AOF CAMDEN, NEW JERSEY,

'A CORPORATION OF NEW JERSEY RADIO PICK-UIP SYSTEM Appueation mea Maren 11,

This invention relates to a system for picking up radio energy, and serves as a substitute for the usual antenna or loop circuit.

In my prior application, Serial No. 50,478, entitled Radio receiving system and filedAugust 15, 1925, I describe a receiver circuit in which a part thereof, exclusive of the radio frequency circuit, acts as one Vcapacity area of. an open absorbingcircuit; and I specically describe how the loud speaker or either of the batteries can be so utilized.v My present application is a continuation in part of this earlier application, and is intended to cover certain alternative embodiments some of ywhich only, are shown in the earlier application.

It is one of the objects of my invention, therefore, to make it possible to eliminate the usual antenna or loop.

It has been proposed in the past to utilize all of the receiver circuits as a capacity area; lbut sucha system is notV practical in a multitube set for several reasons. One is that tuning of such a set would be difficult, due to the effects of body capacity; and another is that it is disadvantageous not to shield the radio frequency circuits, especially when a number of radio frequency stages are used. Such shielding of course would effectively prevent lthe absorption of any energy at all inthe system. With my arrangement, such shielding can be retained, and yet a portion of the system that is not shielded can be used as a capacity area. In this way, a very selective and sensitive circuit can be obtained.

My invention possesses many other advantages, and has other objects which may be made more easily apparent from a consideration of. several embodiments of my invention.

For this purpose I have shown a few forms in the drawings accompanying and forming part of the present speciication. I shall now proceed'to describe these forms in detail, which illustrate the general principles of my inven- V tion; but it is to ber understood that this de- 1927. serial No. 174,456. c

tailed description is not to be taken in a limiting sense, since the scope yof my'invention is best definedby the appended claims.

Referring to the drawings: Figure 1 is a front view of a radio set showing one form of my invention;

Fig. 2 is a wiring Vdiagram thereof; and Figs. 3, 4, and 5 are diagrams of other embodiments of my invention.

In Fig. 1 I show a cabinet 11 intended to house a radio set; and adjacentthereto or supported thereon, an electric lamp 12 of the usual table variety, for casting a light on the set. In this form of my invention, I utilize the metal parts of the lamp as a capacity area to provide an open circuit pick-up system. This is accomplished by the aid of a system of connections which is exemplified in Fig. 2.

In this figure, I show a common type of radio set circuit, including one or more radio frequency amplifier stages, such as 13, each of which can have a tunable circuit 14 to whichV a pick-up circuit can be coupled. rlhen there is the usual detector stage 15, and onev or more audio frequency stages 16, the V -last one of which has, invits output circuit, a translating device, such las loud-speaker 17. All this is shown merely diagrammatically since such circuits are well-known, and I do not'd-esire to limit myself to any particular variety, although. ink substantially all forms, so-called audions 18 and 19 or their equivalents are used to previdethe detecting and 4vamplifying' functions. l. c

I shall now describe how a pick-up system is formed with the lamp 12 providing a capacity area. rIheI 4lamp is shown as fed 4through a plug 2O adapted to be inserted into the usual outlet,.and twin conductors 21. The capacity between this supply circuit, and the Se Vmetallic isolated partsof the'lamp, such as the metal base, is indicated by the condensers Y22. The twin conductors 21 are formed into a coil 23 which is coupledv to coil 24 of the tunable circuit Since both conductors are 9c Vlamp support, ywhich portion .is insulated from the usual! current carrying parts of the lamp 12. This conductor 25 has a coil 26 in series therewith, which is inductively coupled to circuit 14; and a ground 27 completes this supplementary pick-up system.

Y In Fig. 3 I disclose a scheme whereby the'B battery or B battery .eliminator 28 serves to 'provide a capacity area for an open circuit Vpick-up system. vThe amplifying and'detecting system is shown diagrammatically at 29 and 30, and the loudspeaker or phones at 31. The leads 35 from battery 28 or its equivalent (three leads in this instance) connect to appropriate posts 32, 33 and 34 of the set. The triple conductor 35 is formed into an inductance coil 36 coupled to coil 37 of the tunable circuit 29. The pick-up system is thus formed by the metallic mass of element 28, coil 36, and ground 38 provided on the set.

It is also possible to use other elements for providing the capacity area. Thus in Fig. 4, I utilize the source of electrical energy 39 for Y the filamentafor this purpose. This can be a storage battery or its equivalent. The amplifying and detecting system is similar to that already discussed. The source 39, instead of being directly connected across the filaments 40, 41, and 42 of the various thermioiiic devices, includes preferably a portion of f the coil 43 of the tunable circuit'44, as well as a choke coil 45 to prevent radio frequency currents from flowing directly to ground.

VThe inclusion of a portion of coil 43 serves as a coupling between the pick-up system and the input sideof the system. Y l

The pick-up systemincludes element 39, a portion of coil 43 and 39 serves as a capacity area.

In Fig. 5, I showstill another form of my invention. The amplifying and detecting system` is similar to those already described, and includes the tunable circuit47 with its coil'48. VIn this instance, an A and B battery eliminator 49 is used, from which leads 50 extend to the appropriate elements of the set. This eliminator is shown as fed from mains 51 through an iron cored transformer52, the core 53 of which is grounded at 54. In orderto form the open circuit pickup` system, the leads V51 are formedinto a double wound coil 55 which iscoupled to ground 46, Element coil 48. The distributed capacity between core 53 and the primary winding 56 of transformer 52 is represented by condensers 57 and 58. The pick-up system thus includes lines 51, coil 55, capacities 57 and 58, core 53 and ground 54. Due to the twin conductor wining of coil 55, the power hum is compensate In all the forms of my invention herein illustrated, 'some element of the power supply is utilized to provide a capacity'area for the pick-up system.

I claim:

1. In a radio receiving system,`means-for Y receiving electrical impulses 'and acting upon the received impulses to make them perceptible, saidineans including devices to which electrical energy must be passed, means fo-r supplying electrical energy to said devices, saidmeans including a plurality of-leads formed into a multiple conductor transformer winding coupled to the input side of the system, and means providing 'a counterpoise for' that partof the supplying means which connects to the leads to form an absorbing circuit.'

2. Inv a radioreceiving system, means for receiving electrical impulses and acting upon the received impulses to'make them perceptible, said means including one or more electronic emission devices, meansv for supplying electrical energy to said'devices, said means including a pair of leads wound to forma twin conductor transformer winding coupled to the receiving means, Aand means providing a counterpoise for that part of the Y supplying means that connects to the leads tronic emission devices, saidY devices requiring electrical energy for their operation, a device for modifying electrical energy to a form suitable for supplying said required electrical energy and connected to said electronic emission devices, a transformer transmitting energy to said modifyingdevice, and a pair 0f conductors connected to the primary of the transformer and forming a transformer coil liics i coupled to the receivinglmeans, said conductor being arranged to be connected to a source of energy, whereby at least some -of the coniiections to said Lsource serve as a capacity] area for an openv circuit picloup system that is coupled to the receiving means.

4. The combination 'as set forth in claim 3, the transformer having a core which is grounded, to form a counterpoise for the capacity area. Y f

5. The combination as set forth in claim 3, in which the coupling ofthe leadsto the receiving means is eifected by a coupling coil my hand.

HAROLD F. ELLIOTT. 

